FAIR VALUE MEASUREMENTS (Change in Fair Value at Level 3) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Change in Fair Value Measurement Categorized in Level 3 [Roll Forward]
Transfers into Level 3	$ 0			$ 0
Transfers out of Level 3		$ 0	$ 0
Contingent Consideration
Change in Fair Value Measurement Categorized in Level 3 [Roll Forward]
Balance at beginning of period	29,500,000	24,300,000	0	0
Additions	0	0	0	77,300,000
Accretion on discounted liabilities	0	1,500,000	0	1,500,000
Settlements	0	400,000	0	400,000
Unrealized (gain) loss included in earnings	(5,200,000)	(13,800,000)	24,300,000	(66,800,000)
Balance at end of period	$ 24,300,000	$ 12,400,000	$ 24,300,000	$ 12,400,000